One person sustained non life-threatening injuries after a large chunk of railing from a bridge collapsed Monday onto a busy underpass in Chattanooga, Tenn.

Chattanooga Mayor Andy Berke posted a photo of the collapse on Twitter, writing: “A frightening bridge collapse at one of the most heavily trafficked intersections in the country, where 75 and 24 meet. Truly miraculous that no one was seriously injured. [The Tennessee Department of Transportation] is one [sic] the scene assessing cause and traffic solutions.”

Officials from the Tennessee Department of Transportation have not yet determined the cause of the 11:30 a.m. collapse, but said it is confident that the rest of the bridge is structurally sound.

The bridge, which supports the southbound lane of Interstate 75, is expected to reopen Monday night after a barrier is set up blocking the side of the bridge that collapsed and allowing traffic to continue in the other lane.

The bridge was last inspected last year and was found to have nothing structurally wrong with it. Officials will be investigating Monday’s collapse to determine a cause.